Dom Farrell

Pep Guardiola's Manchester City is favored to retain its Premier League crown this season after storming to glory with a record-breaking 100-point haul last time around.

It has been an offseason of quiet consolidation at the Etihad Stadium, with record signing Riyad Mahrez coming in to bolster an already formidable side, which looked in fine order during Sunday's comfortable 2-0 win over Chelsea in the Community Shield.

But such a position of apparent strength has proved cruelly deceptive for reigning champions in England over the past decade.

Manchester United was the last club to win back-to-back league titles when it made it three in a row in 2008-09. Since then it has been a story of near-misses at best to outright implosions at worst.

Chasing an unprecedented fourth consecutive title proved a bridge too far for Alex Ferguson's men, with Cristiano Ronaldo and Carlos Tevez's respective departures to Real Madrid and Manchester City taking a toll despite Wayne Rooney excelling. A broken metatarsal ruled Rooney out of the pivotal 2-1 defeat to Carlo Ancelotti's Chelsea at Old Trafford in April. The loss was a contentious one for United as Didier Drogba fired the Blues' crucial second from an offside position in the 79th minute

Ancelotti's side began in rip-roaring fashion, posting back-to-back 6-0 wins over West Brom and Wigan Athletic in its opening two matches and winning each of the first five league games, conceding only once. A 1-0 loss at Manchester City in September checked that momentum and Chelsea's form collapsed entirely as it won two and lost five of 11 matches between Nov. 7 and Jan. 5. Fernando Torres' big-money midseason arrival proved more of a hindrance than a help and United effectively regained its title with a rousing 2-1 defeat of the Blues in May.

No side has come closer to retaining the Premier League during this period than United in 2011-12, missing out as it did on goal difference when Sergio Aguero hauled Manchester City past Queens Park Rangers in the season's unforgettable last act. City stormed into a handy lead — beating United 6-1 at Old Trafford in October — early in the season before United closed the gap at midway. The battle seemed to have turned decisively in the Red Devils' direction when they led by eight points with six games remaining, but then came a collapse entirely uncharacteristic of the Ferguson years.

City was unbeaten in the Premier League until Robin van Persie scored a last-gasp Manchester derby winner in December. The Dutch striker plumped for United over its rivals when leaving Arsenal before the start of the campaign and he remained a pivotal figure — firing Ferguson to his 13th and final Premier League title with 26 goals, while Roberto Mancini's frustration over City's misses in the transfer market simmered as the title defense unraveled. A 1-0 FA Cup final defeat to Wigan Athletic saw Mancini sacked before the final two games of the season.

Beginning the modern trend for champions not only failing to defend their crown but collapsing at a distance from the title picture, David Moyes' dream job and a six-year contract ended before the season was out. A 2-0 defeat to former club Everton in April ended any faint hope of United qualifying for the Champions League and the Old Trafford board had seen enough as Liverpool and eventual winner Manchester City took the Premier League race to the wire.

Jose Mourinho ensured the previous year enjoyed a three-horse race for the Premier League until the closing weeks and, even then, Chelsea managed to land a body blow against Liverpool's ambitions. Bolstered by the arrivals of Cesc Fabregas and Diego Costa, the Blues looked a cut above from the off and, although Manuel Pellegrini's side closed the gap around the midway point of the season, City rarely made a strong case for being back-to-back champions. Pellegrini's complaints over the impact of Financial Fair Play punishments might have carried more weight had he not wasted £42 million on the accident-prone Eliaquim Mangala.

Mourinho had established a reputation of his teams falling away during his third season in charge but no one could have foreseen the abject shambles of his Chelsea during the second half of 2015. The public lambasting of club doctor Eva Carneiro set a worrying tone as a cycle of damaging defeats and embittered public utterances from Mourinho became the norm. The final act came with a 2-1 defeat to Leicester City — Claudio Ranieri's band of merry men on their way to one of the all-time shocking sporting triumphs — that left Chelsea a point above the relegation zone. Guus Hiddink came in to steady the ship.

The nature of Leicester's improbable fairytale title win meant a repeat was never in the cards. But the Foxes hurtling toward the relegation zone and Claudio Ranieri being sacked amid accusations of player betrayal jarred horribly. Ranieri's exit in February left a bitter taste, although Craig Shakespeare successfully guided the Foxes away from the drop zone as Chelsea recovered from its own nightmare defense to romp to the title.

Complaints about transfer policy, fallouts with major players and a public dispute — Antonio Conte unwittingly compiled a "greatest hits" of the factors to have undermined recent title defenses as Chelsea finished outside the Champions League places last season. Beating Mourinho and Manchester United at Wembley in the FA Cup final came with too much damage done for his job to be saved.